Microsoft today tried to gather momentum for Dynamic HTML, a new
technology spearheaded by Microsoft for making Web pages more interactive. Dynamic HTML will be a core feature of Internet Explorer 4.0, and today the company announced that a handful of tool vendors, including Macromedia, Powersoft, and Borland International, have pledged to support it in their development pacakges.

But it remains unclear whether Microsoft's Dynamic HTML will be fully compatible with a similar technology Netscape is including in its upcoming Communicator.

To make matters even more confusing for developers, Netscape recently renamed its technology "dynamic HTML." That's the same name as Microsoft but with a lowercase "d."

Microsoft's Dynamic HTML--with a capital "D"--is designed to work with existing Web page standards such as HTML 3.2 and cascading style sheets. By using scripting languages such as VisualBasic Script and JavaScript, Microsoft says developers will be able to create Web pages that respond to a user's actions. For example, a table of contents on a page would expand or contract when the user passes the cursor over a headline.

"It's designed to let developers create Web pages that are comparable to CD-ROM content," said Tom Johnston, group product manager at Microsoft.

Netscape has exactly the same goal for its dynamic HTML: Web pages that respond to the user. But it uses a slightly different collection of technologies to reach that end, namely HTML, layers, absolute positioning, and JavaScript stylesheets.

But the two companies can't say really to what extent the two versions will work together. With such a hodgepodge of different technologies, the likelihood of incompatibilities creeping in is high unless the two companies make an effort to collaborate.

Microsoft's Johnston said that the company has submitted its version of Dynamic HTML to the World Wide Web Consortium to try and establish its vision as an official standard.

Netscape representatives say they don't entirely understand what it is that Microsoft is calling "Dynamic HTML" and so can't say if Netscape would support such a standard.

If the companies end up supporting two different approaches to interactive Web pages, it will put Web site developers and tool vendors in a bind. Everyone would be forced to pick one over the other and risk alienating the users of the competing browser or go to the trouble of designing their sites for both Communicator and Explorer 4.0. The version that attracts more developer support will become the de facto standard, no matter what the W3C says.

Microsoft's announcement today of support from tool developers is about gaining an early advantage in this potential fight.

There is little doubt Netscape will try to counter this with its own set of endorsements from toolmakers. Stay tuned.